1. Field of the Invention
The present invention relates to an information record apparatus and method, as well as an information reproduction apparatus and method, such as a DVD recorder or a DVD player. The present invention further relates to a computer program product to make a computer function as such an information record apparatus and the like.
2. Description of the Related Art
At present, terrestrial digital broadcasting, BS digital broadcasting, and the like have been already begun, so that audio-visual environment presenting a high quality digital broadcasting becomes more popular even at home. In such a kind of digital broadcasting, it is possible to enjoy content information having quality of high vision broadcasting (hereinafter referred to as HD (High Definition)) or HDTV, superior to content information having quality of so-called standard broadcasting (hereinafter referred to as SD (Standard Definition)) or SDTV.
On the other hand, since the content information broadcasted by such a kind of digital broadcasting is digital data, the copying of the content information does not tend to deteriorate the image quality. Thereby, the copying is easy. For this reason, the copying of the digital data (or the content information of the digital broadcasting) makes a problem in protecting the copyright. In order to protect the copyright, various approaches for protecting the copyright is on their development, as disclosed in Japanese Patent Application Laid-Open Nos. 2000-324443, 2000-298926 and Hei 9-171658, for example. Particularly, CPPM (Content Protection for Prerecorded Media) or CPRM (Content Protection for Recording Media) employed in a record medium such as the DVD or the like for protecting the copyright is a technology for preventing an illegal or unauthorized copying, in which the copyright of the content may be appropriately protected by putting a “copy once limitation” on the content information.